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rp: update rp-pac.

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This commit is contained in:
Dario Nieuwenhuis
2023-06-16 01:32:18 +02:00
parent 64e3310e64
commit 837ebe405f
22 changed files with 1239 additions and 1493 deletions
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70
embassy-rp/src/float/div.rs
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@ -17,45 +17,43 @@ where
{
let sio = rp_pac::SIO;
unsafe {
// Since we can't save the signed-ness of the calculation, we have to make
// sure that there's at least an 8 cycle delay before we read the result.
// The Pico SDK ensures this by using a 6 cycle push and two 1 cycle reads.
// Since we can't be sure the Rust implementation will optimize to the same,
// just use an explicit wait.
while !sio.div().csr().read().ready() {}
// Since we can't save the signed-ness of the calculation, we have to make
// sure that there's at least an 8 cycle delay before we read the result.
// The Pico SDK ensures this by using a 6 cycle push and two 1 cycle reads.
// Since we can't be sure the Rust implementation will optimize to the same,
// just use an explicit wait.
while !sio.div().csr().read().ready() {}
// Read the quotient last, since that's what clears the dirty flag
let dividend = sio.div().udividend().read();
let divisor = sio.div().udivisor().read();
let remainder = sio.div().remainder().read();
let quotient = sio.div().quotient().read();
// Read the quotient last, since that's what clears the dirty flag
let dividend = sio.div().udividend().read();
let divisor = sio.div().udivisor().read();
let remainder = sio.div().remainder().read();
let quotient = sio.div().quotient().read();
// If we get interrupted here (before a write sets the DIRTY flag) its fine, since
// we have the full state, so the interruptor doesn't have to restore it. Once the
// write happens and the DIRTY flag is set, the interruptor becomes responsible for
// restoring our state.
let result = f();
// If we get interrupted here (before a write sets the DIRTY flag) its fine, since
// we have the full state, so the interruptor doesn't have to restore it. Once the
// write happens and the DIRTY flag is set, the interruptor becomes responsible for
// restoring our state.
let result = f();
// If we are interrupted here, then the interruptor will start an incorrect calculation
// using a wrong divisor, but we'll restore the divisor and result ourselves correctly.
// This sets DIRTY, so any interruptor will save the state.
sio.div().udividend().write_value(dividend);
// If we are interrupted here, the the interruptor may start the calculation using
// incorrectly signed inputs, but we'll restore the result ourselves.
// This sets DIRTY, so any interruptor will save the state.
sio.div().udivisor().write_value(divisor);
// If we are interrupted here, the interruptor will have restored everything but the
// quotient may be wrongly signed. If the calculation started by the above writes is
// still ongoing it is stopped, so it won't replace the result we're restoring.
// DIRTY and READY set, but only DIRTY matters to make the interruptor save the state.
sio.div().remainder().write_value(remainder);
// State fully restored after the quotient write. This sets both DIRTY and READY, so
// whatever we may have interrupted can read the result.
sio.div().quotient().write_value(quotient);
// If we are interrupted here, then the interruptor will start an incorrect calculation
// using a wrong divisor, but we'll restore the divisor and result ourselves correctly.
// This sets DIRTY, so any interruptor will save the state.
sio.div().udividend().write_value(dividend);
// If we are interrupted here, the the interruptor may start the calculation using
// incorrectly signed inputs, but we'll restore the result ourselves.
// This sets DIRTY, so any interruptor will save the state.
sio.div().udivisor().write_value(divisor);
// If we are interrupted here, the interruptor will have restored everything but the
// quotient may be wrongly signed. If the calculation started by the above writes is
// still ongoing it is stopped, so it won't replace the result we're restoring.
// DIRTY and READY set, but only DIRTY matters to make the interruptor save the state.
sio.div().remainder().write_value(remainder);
// State fully restored after the quotient write. This sets both DIRTY and READY, so
// whatever we may have interrupted can read the result.
sio.div().quotient().write_value(quotient);
result
}
result
}
fn save_divider<F, R>(f: F) -> R
@ -63,7 +61,7 @@ where
F: FnOnce() -> R,
{
let sio = rp_pac::SIO;
if unsafe { !sio.div().csr().read().dirty() } {
if !sio.div().csr().read().dirty() {
// Not dirty, so nothing is waiting for the calculation. So we can just
// issue it directly without a save/restore.
f()